Recording and reproducing instrument



Jan. 30, 1923.

H. C. MARTIN, RECORDING AND REPRODUCING INSTRUMENT.

FILED JAN. 23. 1922.

Q tbommy Patented Jan. 30, 1923.

UNITED STATES HENRY Ci MARTIN, OF ELKHART, INDIANA.

RECORDING AND REPRODUCING INSTRUMENT.

Application filed January 23, 1922.

To a. Q 710% it may concern Be it known that I, HENRY C. MARTIN, a citizen of the United States of America, residing at Elkhart, in the county oi? Filkhart and State of Indiana, have invented certain new and useful Improvements in Recording and Reproducing Instruments, of which the following is a specification.

The subject matter of the present invention relates particularly to the construction of the sound box and tone arm of the recording or reproducing instrument whereby the sound box may be joined to the tone arm in such manner as to permit facile adjustment of the sound box, its conveyer arms and the needle or stylus, to various and numerous angular positions with relation to the plane of the recording or IGIH'UtluClIlg record or disk. By the utilization of my invention the sound waves or vibrations arising from the conveyer arms through the diaph agni, or passing to the com c-yer arms through the diaphragm, are in the first instance collected in the sound box above the diaphragm and passed therethrough without interference or obstruction to the tone arm. V hen the in strument is recording sounds, the sound waves or vibrations are carried to the sound box above the diaphragm where sufficient space is provided to insure proper and uninterrui ited distrihutiijin ol the sound waves to the diaphragm and to the multiplicity of sound conveyer-arms attached to the (liaphragm. The parts of the sound box and its head are so combined and arranged that the sound box may readily be detached from the tone arm, and may with equal facility be loosened with relation to the tone arm for adjustment to desired angular position, and. may also be "Q idly affixed thereto in desired on. i The tone 1 utilized in i1 with the sound be; c; involv ea'tures of construction whereb; the

Qractions of son n pl1 Mldition lo i'l'n t afi'uf ileiil by their ii through the dome shaped sound box, before the sound waves arrive at the ainplilier proper thus reni'le 'inu llie prmluction ol tones and sound in a inori-v l acilc manner.

In the accoinpuiiyingr drawings I have illustrated one complete example of the physical embodiment of my invention wherein the parts are combined and arranged acco ding to the best mode I have thus "far devised for Serial No. 531,233.

the practical application of the principles of I my invention.

Figure 1 is a view in side elevation ol the sound box in vertical position, or perpendicular to the record dislo showing also the tone arm in section, together with the elbows and joints for supporting the tone arm and sound box.

Figure 2 is a top plan view of the sound. box, detached from the tone arm.

Figure 3 is a vertical sectional through the sound box, showin conveyer arms in elevation. It will be understood that the sound box: is'adapted for use with a revolving c *linder or rotary disk record as usual, and that the stylus or needle travels in the groove tor the repriuluction of sound, and also performs its usual functions in the operatiiin of recording.

The sound box is supported above the disk record by the tone arm de ignated as a whole by the numeral 1. which has a series of elbows a 2, properly artEcnl-atezl and supporteiil on the vertical tubular member 2}. which is connected with the amplifier, not shown. The tone arm is adapted. to swing in a vertical plane with is renter o'r' movement at the elbows am also is designed to swing; in a lmrizmitai piano with its ceno'gr ol movement al 23 in l'hemvertieal tubular member 3. Linear :uljusinient o?" the sound box, toward or awa from li o pivotal cente 2 and :5 may be accomplished by extending or contracting the tone arm which includes an inner tubular section l thatmay be moved relatively to it miter casing 1. This adjustment of the l;.? gth of the tone arm brings the voice. or sound from the sound producing (le ice to be recorded closer to the diaphramn of the sound box and the record, to i1 we the force of the vibrations at the recording point or ice view some 01'' the tion {l o the f icti on I.

ii a

elements at their oi the elbow 8 a second clamp sleeve, 9 is secured, by means oil which the. sound box is connected with the elbow, and this clamp sleeve is also slotted and fashioned with perforated cars 10 and a set screw 11.

The top of the sound box 12 is of metal, open at its center and dome shaped, or spherical with its convex face on the outer side or top and the concave inner portion forms a space for collecting or distributing sound waves or vilnbations for recording and reproducing respectively.

In connection with the spherical top 12 of the sound box I employ a tubular'head 13, secured at its upper end, in alinement with the elbow 8, within'the resilient end of the clamp sleeve 9, and at its lower end this tubular head is fashioned with aflaring, concavo-convex or spherical flange 1 1, its curved lines being struck from the same center as are those of the top or dome shaped portion 12. Between the flange 14 and the inner face of the spherical head 12 is interposed a washer or gasket 15, of felt, leather, or other non-conducting material adapted to be frictionally engaged between these two elements. On its exterior the tubular head 13 is provided with screw threads 16 intermediate its height, that are adapted to receive the nut 17 which is knurled on its exterior for :Zacility inturning. ii metallic washer 18 is located below the nut, and between this washer and spherical head 12 a non-conducting gasket 19 is interposed. The spherical head 12, gaskets 14; and 19, a11d metallic washer 18 have open centeifsythe spherical headespeoially being so fashionet in order that the, latter may be adjusted at any angle (within limits) to the perpendicular, for tilting the sound 'boX. Thus by slightly tiu'ning backward the nut 17 in Figures 1 and 2, the spherical head 12 may be released and the sound box moved to adjusted position. then by tightening the nut the spherical head is clamped and frictionally held between the two gaskets and the flange 14 and washerlS.

Below the flanged. spherical head, a.

tlanged retaining ring 20 secured, by

means of screwsi l passing through-these peripheries, and the dia phragm, '22, preferably of mica, and concavo-convezr in form... secured atits circula]? edges between the flanged ring and a 11on-con 3lucting gasket or ring 23.

There are illustrated live sound transmitting or conveyor arms 24;, having their outer ends brought together at 25, above the needle or stylus 26, and the. upper ends of these arms are connected at 27 with the diaphragm.

' as;30 is interposedbetween the stylusholder 28 and the ends 25 of the arms, the usual set screw 31 being employed for holding the needle.

The arms are joined integrals, as at 25,

. and are of varying lengths bent to bowed shape as shown in order to insure a comparatively long path of travel oil? sound increases from the point of attachment to.

the diaphragm to the junction of the several arms in thestylus-holder. By this variation in size and lengththe arms are adapted to receiveand convey various tones or vibrations.

l-laving thus fully described my invention, whatI claim as new and desire to secure by Letters Patent isi i 1. The combination with a tone arm and a tubular head, ofa-soundbox including an open-center spherical head surroundin -said tubular head, a complementary flange on the tubular head, and means on the tubular head for clamping together the spherical headwith relation: to the flange.

2. Tho-combination in a sound box with its diaphraginiand.an open-center spherical head forming a space above the diaphragm, oia tubularsupportinghead having acomplementary flange witl in said spherical head, and means for clamping saidspherical hea d in adjustedposition onsaidflange.

13.'The combination with a supporting, tubular head having exterior threads. and an annular spherical. flange, of a sound box having an open-center spherical head, and

a nut on the threaded head. whereby said.

nut is adaptedto hold thespherical head in adjusted position on the spherical flange.

tJThecombination with a tone arm and.

and means lfor; securing saidadjusting-head in fixed position with relation; to the tubularhea-d.

5;1hecomb1nat1on with a tone arm, a

detachable elbow having a clamping sleeve, sanda tubular -head tittediu said-s. eve. ex

teriorthreads on-said head and a-spherioal flange at: the/end otfisaid head, an open-cam ter spherical head forming aportion of a sound box, and a clamp nut ionsaid tubular head, whereby said spherical head may be retained in adjusted.position with relation to. said flange. I

In testimony. whereof I aflfix my signature.

anner. c, MARTIN. 

